Least Common Multiple

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Find the *Least Common Multiple* (LCM) of the numbers 405 and 40.

**Answer**

$405=({3}^{4})(5)$

$40=({2}^{3})(5)$

The LCM of 405 and 40 is the product of the largest powers of each prime factor in both.

Thus the LCM of 405 and 40

$=({2}^{3})({3}^{4})(5)$

$=3240$